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Renewable energy sources (RES) are not limited by geologically accumulated reserves. Their use and consumption will not lead to the inevitable depletion of the Earth's reserves, and they do not pollute the environment. The main motive for the accelerated development of renewable energy in Europe, the United States and many other countries is concern for energy independence and environmental safety. Thus, the EU has adopted a program to achieve the contribution of renewable energy sources to the energy balance by 2020 up to 20%, and by 2040 – up to 40%. Renewable energy is characterized by versatility and diversity. In the list of tasks arising in the implementation of renewable energy (RE) projects (except technological and technical), there are issues of assessing the possibility and efficiency of using RES for energy supply to the regions. At the same time, it should be borne in mind that often the user is interested in comprehensive assessments for various types of energy sources. In specific regions, the most effective can be either the use of hybrid power plants, or the creation of thermal power plants using various types of renewable energy. In connection with the complexity of this problem, as well as the geographic “regionality” of renewable energy, the topic of this article becomes possible and relevant. A heat and power plant is proposed for supplying: electricity, hot water, hot air and heating, in which, together with a wind power generator, a double-circuit solar installation, a heat pump, electricity and heat accumulators are used. This installation allows to reduce the cost of heat energy by reducing material consumption and costs of equipment used, to save fossil fuel; produce electricity and supply the surplus to the state power grid; reduce heat load and environmental pollution., Поновлювані джерела енергії (ПДЕ) не обмежені геологічно накопиченими запасами. Їх використання і споживання не призведе до неминучого вичерпання запасів Землі, і вони не забруднюють навколишнє середовище. Основним мотивом прискореного розвитку відновлюваної енергетики в Європі, США і багатьох інших країнах є турбота про енергетичну незалежність і екологічну безпеку. Так, в странах ЄС прийнято програму досягнення вкладу ПДЕ в енергетичний баланс до 2020 року до 20%, а до 2040 р – до 40%. Відновлювана енергетика характеризується багатогранністю, різноманітністю. У переліку завдань, що виникають при реалізації проектів відновлюваної енергетики (ВЕ) (крім технологічних і технічних), залишаються питання оцінки можливості та ефективності використання ПДЕ для енергозабезпечення регіонів. Одночасно слід враховувати, що найчастіше користувача цікавлять комплексні оцінки з різних видів джерел енергії. У конкретних регіонах найбільш ефективним може стати або використання гібридних енергоустановок, або створення теплоенергетичних установок на різних типах відновлюваної енергії. У зв'язку з комплексністю даної проблеми, а також географічною «регіональністю» відновлюваної енергетики, стає можливим і актуальним тема цієї статті. Пропонується теплоенергетична установка для постачання: електроенергією, гарячою водою, гарячим повітрям і опаленням, в якій спільно з вітроелектрогенератором, двухконтурною сонячною установкою, використовується тепловий насос, акумулятори електроенергії і теплоти. Ця установка дозволяє зменшити собівартість теплової енергії за рахунок зниження матеріаломісткості і витрат на обладнання, економити органічне паливо; виробляти електроенергію і надлишок її віддавати в державну електромережу; зменшити теплове навантаження і забруднення навколишнього середовища.

Laser wakefield accelerators commonly produce on-axis, low-divergence, high-energy electron beams. However, a high charge, annular shaped beam can be trapped outside the bubble and accelerated to high energies. Here we present a parametric study on the production of low-energy-spread, ultra-relativistic electron ring beams in a two-stage gas cell. Ring-shaped beams with energies higher than 750 MeV are observed simultaneously with on axis, continuously injected electrons. Often multiple ring shaped beams with different energies are produced and parametric studies to control the generation and properties of these structures were conducted. Particle tracking and particle-in-cell simulations are used to determine properties of these beams and investigate how they are formed and trapped outside the bubble by the wake produced by on-axis injected electrons. These unusual femtosecond duration, high-charge, high-energy, ring electron beams may find use in beam driven plasma wakefield accelerators and radiation sources.

Active control of chirality in the terahertz frequency range is of great importance in many scientific areas, which include research into fundamental optical phenomena, investigation of novel materials, spectroscopy, imaging, wireless communications and chemistry. The lack of efficient, integrated and fast-reconfigurable polarization modulators has hindered, so far, the full exploitation of applications in all the aforementioned fields. Metamaterials are artificial resonant elements possessing unique remarkable properties such as high efficiency and miniaturization capability. The interplay of metallic metamaterial arrays with electrostatically tunable monolayer graphene has been demonstrated to be a valid approach for the realization of a novel class of THz devices. In this work, the realization of active chiral graphene/metamaterial modulator is presented. The versatility of this experimental approach allowed the device integration with broadband sources such as terahertz time domain spectrometers as well as with quantum cascade lasers. A continuous rotation of the polarization plane > 30° has been reported with a reconfiguration speed > 5 MHz. These results pave the way to the integration of fast terahertz polarization modulators in all the applications where these devices are in great demand.

As enzymes in the outer membrane of the mitochondrion, monoamine oxidases (MAOs) can catalyze the oxidative deamination of monoamines in the human body. According to different substrates, MAOs can be divided into MAO-A and MAO-B. The imbalance of the MAO-A is associated with neurological degeneration, while excess MAO-B activity is closely connected with Parkinson's disease (PD) and Alzheimer's disease (AD); therefore, detection of MAOs is of great significance for the diagnosis and treatment of these diseases. This work reports the multiplexed detection of MAO-A and MAO-B using paper-based devices based on chemiluminescence (CL). The detection limits were 5.01 pg/mL for MAO-A and 8.50 pg/mL for MAO-B in human serum. In addition, we used paper-based devices to detect MAOs in human cells and tissue samples and found that the results of paper-based detection and Western blotting (WB) showed the same trend. While only one antibody can be incubated on the same membrane by WB, multiple antibodies incubated on the same paper enabled simultaneous detection of MAO-A and MAO-B by paper-based devices. The paper-based assay could be used for preliminary early screening of clinical samples for MAOs and can be extended as an alternative to WB for multiplexed detection of various proteins in disease cell or tissue samples.

Trapped-flux magnets comprising stacked superconducting tape constitute a promising development to increase the power density of electrical machines, whilst at the same time keeping the complexity required in their construction in manageable levels that allow their use in applications such as aircraft propulsion. However, the conditions in which superconducting stacks operate inside an electrical motor differ quite significantly from the materials characterization experiments commonly developed to model their behaviour. This work presents the results of studying the applicability of these devices as magnetic flux source in the rotor of synchronous machines considering the influence of whole magnetic circuit. Several aspects are assessed, such as flux harmonics, magnetization, losses and demagnetization. Analytical expressions, which provide limited accuracy but allow fast calculations, are used for this purpose. The results illustrate the different trade-offs that arise during the design of a synchronous electric motor using trapped-flux magnets.

Significance: Two-photon microscopy has become the standard platform for deep-tissue fluorescence imaging. However, the use of point scanning in conventional two-photon microscopy limits the speed of volumetric image acquisition. Aim: To obtain fast and deep volumetric images, we combine two-photon light sheet fluorescence microscopy (2p-LSFM) and axicon imaging that yields an extended depth of field (DOF) in 2p-LSFM. Approach: Axicon imaging is achieved by imposing an axicon lens in the detection part of LSFM. Results: The DOF with axicon imaging is extended more than 20-fold over that of a conventional imaging lens, liberating the synchronized scanning in LSFM. We captured images of dynamic beating hearts and red blood cells in zebrafish larvae at volume acquisition rates up to 30 Hz. Conclusions: We demonstrate the fast three-dimensional imaging capability of 2p-LSFM with axicon imaging by recording the rapid dynamics of physiological processes.

Today, ethyl alcohol is widely used in many industries. Ethanol production processes from any organic matter often involve rectification, which is an energy-intensive process. The constant increase in the cost of energy leads to a significant growth of the cost of production. Reducing the unit energy consumption can solve a range of important issues: first, that of decreasing production cost, and secondly, that of nationwide dependence on external energy suppliers. A detailed analysis of the thermal energy potential of technological flows aimed at solving the problem of reducing energy consumption inspires the development of more energy-efficient solutions for organizing this processes. The search for alternative solutions demonstrates that one of the methods of reducing the unit energy consumption for ethanol production, in particular one that does not require a total restructuring of the production lines, is the method of integration of processes based on pinch analysis. The extraction of these technological flows was carried out on the basis of the regulatory documentation of the hardware-technological scheme of the centralized ethyl alcohol head fraction distillation plant and the energy audit report of that plant, which was carried out at one of the alcohol enterprises of Ukraine. A distillation and a purification column were selected from the centralized ethyl alcohol distillation plant for thermal integration of the existing process. The thermal and material balances of the ethyl alcohol head fraction distillation plant columns were calculated. To maximize the energy potential of the heat flows, the principles of pinch design were applied and a grid diagram of heat exchanger networks was designed. To maximize the recovery of thermal energy, the difference ΔTmin was set to - 3ºC. This led to the need to use energy-efficient heat exchange equipment. A significant reduction in the use of external utilities (by 48% for cold utilitie and by 38% for hot utilitie) for selected heat flows and a short payback period for the project (approximately three months) makes this solution viable., На сьогодні етиловий спирт є речовиною, використання якої поширено у багатьох галузях промисловості. Технологія виробництва етанолу з будь-якої органічної сировини найчастіше включає ректифікацію, яка є енергоємним процесом. Висока ціна енергоносіїв і постійне її зростання призводять до суттєвого збільшення вартості продукції. Зменшення питомих витрат енергії на одиницю продукції може вирішити комплекс питань: по-перше, зменшити собівартість продукції, по-друге, в масштабах держави, полегшити енергозалежність від зовнішніх постачальників енергії. Детальний аналіз енергетичного потенціалу технологічних потоків з метою вирішення задачі зменшення енерговитрат надихає на розробку більш енергоефективних рішень організації цього процесу. Пошук альтернативних рішень демонструє, що одним з методів зменшення питомих витрат енергії на виробництво етанолу, зокрема таким, що не потребує тотальної реконструкції виробництва, є метод інтеграції процесів, що базується на пінч-аналізі. Екстракція даних технологічних потоків була здійснена на основі регламентної документації апаратурно-технологічної схеми установки централізованої розгонки ГФЕС (головної фракції етилового спирту) та звіту з енергоаудиту даної установки, який був здійснений на одному з спиртових підприємств України. Для теплової інтеграції існуючого процесу, було обрано дві колони установки централізованої розгінки етилового спирту :бражну та епюраційну. Були розраховані тепловий та матеріальний баланси цих колон установки ГФЕС. Для максимальної реалізації енергетичного потенціалу технологічних потоків, були використані принципи пінч-проектування та спроектовано сіткову діаграму. Для максимізації рекуперації теплової енергії було задано ΔТmin - 3ºС. Це призвело до необхідності використання енергоефективного теплообмінного обладнання. Суттєве зменшення використання зовнішніх утиліт (холодних на 48% та гарячих – на 38%) для обраних технологічних потоків та невеликий термін окупності проекту (близько трьох місяців) робить доцільним використання такого роду рішення проблеми.

We describe a laser-plasma platform for photon-photon collision experiments to measure fundamental quantum electrodynamic processes such as the linear Breit-Wheeler process with real photons. The platform has been developed using the Gemini laser facility at the Rutherford Appleton Laboratory. A laser wakefield accelerator and a bremsstrahlung convertor are used to generate a collimated beam of photons with energies of hundreds of MeV, that collide with keV x-ray photons generated by a laser heated plasma target. To detect the pairs generated by the photon-photon collisions, a magnetic transport system has been developed which directs the pairs onto scintillation-based and hybrid silicon pixel single particle detectors. We present commissioning results from an experimental campaign using this laser-plasma platform for photon-photon physics, demonstrating successful generation of both photon sources, characterisation of the magnetic transport system and calibration of the single particle detectors, and discuss the feasibility of this platform for the observation of the Breit-Wheeler process. The design of the platform will also serve as the basis for the investigation of strong-field quantum electrodynamic processes such as the nonlinear Breit-Wheeler and the Trident process, or eventually, photon-photon scattering. We describe a laser–plasma platform for photon–photon collision experiments to measure fundamental quantum electrodynamic processes. As an example we describe using this platform to attempt to observe the linear Breit–Wheeler process. The platform has been developed using the Gemini laser facility at the Rutherford Appleton Laboratory. A laser Wakefield accelerator and a bremsstrahlung convertor are used to generate a collimated beam of photons with energies of hundreds of MeV, that collide with keV x-ray photons generated by a laser heated plasma target. To detect the pairs generated by the photon–photon collisions, a magnetic transport system has been developed which directs the pairs onto scintillation-based and hybrid silicon pixel single particle detectors (SPDs). We present commissioning results from an experimental campaign using this laser–plasma platform for photon–photon physics, demonstrating successful generation of both photon sources, characterisation of the magnetic transport system and calibration of the SPDs, and discuss the feasibility of this platform for the observation of the Breit–Wheeler process. The design of the platform will also serve as the basis for the investigation of strong-field quantum electrodynamic processes such as the nonlinear Breit–Wheeler and the Trident process, or eventually, photon–photon scattering.

Significance: High-speed three-dimensional (3D) super-resolution microscopy is a unique tool to investigate various biological phenomena; yet the technology is not broadly adopted due to its high cost and complex system design. Aim: We present a compact, low-cost, and high-speed 3D structured illumination microscopy (SIM) based on a digital micromirror device and binary holography to visualize fast biological events with super-resolution. Approach: The 3D SIM uses a digital micromirror device to generate three laser foci with individually controllable positions, phases, and amplitudes via binary holography at the back aperture of objective lens to form optimal 3D structured patterns. Fifteen raw images are sequentially recorded and processed by the 3D SIM algorithm to reconstruct a super-resolved image. Results: Super-resolution 3D imaging at a speed of 26.7 frames per second is achieved with a lateral and axial resolution of 155 and 487 nm, which corresponds to a 1.65- and 1.63-times resolution enhancement, respectively, comparing with standard deconvolution microscopy. Conclusions: The 3D SIM realizes fast super-resolution imaging with optimal 3D structured illumination, which may find important applications in biophotonics.

Significance: The Cherenkov emission spectrum overlaps with that of ambient room light sources. Choice of room lighting devices dramatically affects the efficient detection of Cherenkov emission during patient treatment. Aim: To determine optimal room light sources allowing Cherenkov emission imaging in normally lit radiotherapy treatment delivery rooms. Approach: A variety of commercial light sources and long-pass (LP) filters were surveyed for spectral band separation from the red to near-infrared Cherenkov light emitted by tissue. Their effects on signal-to-noise ratio (SNR), Cherenkov to background signal ratio, and image artifacts were quantified by imaging irradiated tissue equivalent phantoms with an intensified time-gated CMOS camera. Results: Because Cherenkov emission from tissue lies largely in the near-infrared spectrum, a controlled choice of ambient light that avoids this spectral band is ideal, along with a camera that is maximally sensitive to it. An RGB LED light source produced the best SNR out of all sources that mimic room light temperature. A 675-nm LP filter on the camera input further reduced ambient light detected (optical density > 3), achieving maximal SNR for Cherenkov emission near 40. Reduction of the room light signal reduced artifacts from specular reflection on the tissue surface and also minimized spurious Cherenkov signals from non-tissue features such as bolus. Conclusions: LP filtering during image acquisition for near-infrared light in tandem with narrow band LED illuminated rooms improves image quality, trading off the loss of red wavelengths for better removal of room light in the image. This spectral filtering is also critically important to remove specular reflection in the images and allow for imaging of Cherenkov emission through clear bolus. Beyond time-gated external beam therapy systems, the spectral separation methods can be utilized for background removal for continuous treatment delivery methods including proton pencil beam scanning systems and brachytherapy.

Relativistic quantum systems exhibit unique features not present at lower energies, such as the existence of both particles and antiparticles, and restrictions placed on the system dynamics due to the light cone. In order to understand what impact these relativistic phenomena have on the performance of quantum thermal machines we analyze a quantum Otto engine with a working medium of a relativistic particle in an oscillator potential evolving under Dirac or Klein-Gordon dynamics. We examine both the low-temperature, non-relativistic and high-temperature, relativistic limits of the dynamics and find that the relativistic engine operates with higher work output, but an effectively reduced compression ratio, leading to significantly smaller efficiency than its non-relativistic counterpart. Using the framework of endoreversible thermodynamics we determine the efficiency at maximum power of the relativistic engine, and find it to be equivalent to the Curzon-Ahlborn efficiency., 22 pages, 8 figures

HFE-7100 is a routine carrier solvent in amino acid-sensitive fingermark detection reagents such as ninhydrin and 1,2-indanedione/zinc chloride (IND/Zn). However, a potential EU ban on hydrofluoroethers may require reformulation of these treatments worldwide. Solstice® PF has shown promise as a replacement for HFE-7100 in the United Kingdom. However, the performance (and hence optimal formulation) of IND/Zn is impacted by differences in climate and substrate composition, necessitating assessments under local conditions for different regions. We present a series of preliminary investigations in an Australian context, using the IND/Zn formulation used by Australian forensic service providers. The general performance of Solstice® PF-based IND/Zn was comparable to that using HFE-7100 on three substrate types, three ageing periods (1, 7 and 30 days) and 5 donors. However, slight differences in colour and luminescence intensity, as well as increased ink diffusion, suggest chemical interactions with other reagent components that may affect stability. Specifically, Solstice® PF-based reagent formed a precipitate within a month of storage, though this did not affect performance over a 4 month period. HFE-7100-based IND/Zn was found to be marginally more effective than Solstice® PF when applied to incidental fingermarks. These results indicate that Solstice® PF is a satisfactory alternative carrier solvent to HFE-7100 in an Australian context, though users should be aware of possible limitations regarding compatibility with other evidence components (particularly inks) and shelf-life.

Significance: Complementary absorption and fluorescence contrast could prove useful for a wide range of biomedical applications. However, current absorption-based photoacoustic microscopy systems require the ultrasound transducers to physically touch the samples, thereby increasing contamination and limiting strong optical focusing in reflection mode. Aim: We sought to develop an all-optical system for imaging cells and tissues using the three combined imaging modalities: photoacoustic remote sensing (PARS), epifluorescence, and confocal laser scanning microscopy (CLSM). Approach: A PARS subsystem with ultraviolet excitation was used to obtain label-free absorption-contrast images of nucleic acids in ex vivo tissue samples. Co-integrated epifluorescence and CLSM subsystems were used to verify the 2D and 3D nuclei distribution. Results: Complementary absorption and fluorescence contrast were demonstrated in phantom imaging experiments and subsequent cell and tissue imaging experiments. Lateral and axial resolution of ultraviolet-PARS (UV-PARS) is shown to be 0.39 and 1.6 μm, respectively, with 266-nm light. CLSM lateral and axial resolution was measured as 0.97 and 2.0 μm, respectively. This resolution is sufficient to image individual cell layers with fine optical sectioning. UV-PARS images of cell nuclei are validated in thick tissue using CLSM. Conclusions: Multimodal absorption and fluorescence contrast are obtained with a non-contact all-optical microscopy system for the first time and utilized to obtain images of cells and tissues with subcellular resolution.

Significance: The highest absorption peaks of the main components of bone are in the mid-infrared region, making Er:YAG and CO2 lasers the most efficient lasers for cutting bone. Yet, studies of deep bone ablation in minimally invasive settings are very limited, as finding suitable materials for coupling high-power laser light with low attenuation beyond 2 μm is not trivial. Aim: The first aim of this study was to compare the performance of different optical fibers in terms of transmitting Er:YAG laser light with a 2.94-μm wavelength at high pulse energy close to 1 J. The second aim was to achieve deep bone ablation using the best-performing fiber, as determined by our experiments. Approach: In our study, various optical fibers with low attenuation (λ=2.94 μm) were used to couple the Er:YAG laser. The fibers were made of germanium oxide, sapphire, zirconium fluoride, and hollow-core silica, respectively. We compared the fibers in terms of transmission efficiency, resistance to high Er:YAG laser energy, and bending flexibility. The best-performing fiber was used to achieve deep bone ablation in a minimally invasive setting. To do this, we adapted the optimal settings for free-space deep bone ablation with an Er:YAG laser found in a previous study. Results: Three of the fibers endured energy per pulse as high as 820 mJ at a repetition rate of 10 Hz. The best-performing fiber, made of germanium oxide, provided higher transmission efficiency and greater bending flexibility than the other fibers. With an output energy of 370 mJ per pulse at 10 Hz repetition rate, we reached a cutting depth of 6.82±0.99 mm in sheep bone. Histology image analysis was performed on the bone tissue adjacent to the laser ablation crater; the images did not show any structural damage. Conclusions: The findings suggest that our prototype could be used in future generations of endoscopic devices for minimally invasive laserosteotomy.

Significance: Artificial skin (AS) is widely used in dermatology, pharmacology, and toxicology, and has great potential in transplant medicine, burn wound care, and chronic wound treatment. There is a great demand for high-quality AS product and a non-invasive detection method is highly desirable. Aim: To quantify the constructure parameters (i.e., thickness and surface roughness) of AS samples in the culture cycle and explore the growth regularities using optical coherent tomography (OCT). Approach: An adaptive interface detection algorithm is developed to recognize surface points in each A-scan, offering a rapid method to calculate parameters without constructing OCT B-scan pictures and further achieving realizing real-time quantification of AS thickness and surface roughness. Experiments on standard roughness plates and H&E-staining microscopy were performed as a verification. Results: As applied on the whole cycle of AS culture, our method’s results show that during the air–liquid culture, the surface roughness of the skin first decreases and then exhibits an increase, which implies coincidence with the degree of keratinization under a microscope. And normal and typical abnormal samples can be differentiated by thickness and roughness parameters during the culture cycle. Conclusions: The adaptive interface detection algorithm is suitable for high-sensitivity, fast detection, and quantification of the interface with layered characteristic tissues, and can be used for non-destructive detection of the growth regularity of AS sample thickness and roughness during the culture cycle.

Divertor monitoring pulses (DiMPle) have been run in JET from the C35 campaign onwards. They provide an opportunity to study the impurity contamination of the plasma when it is limited by different surfaces within the machine, as well as the longer term behaviour of the impurities. In these discharges the plasma is first limited on the outer wall, then on the inner wall and, subsequently, in the X-point configuration the outer strike point is positioned on the horizontal tile 5 of the machine followed by tile 6 and then the vertical tile 7. The present study details the impurity behaviour in the DiMPle pulses from JET-ILW campaigns C35 to C38, which ran from 2015 to 2019. The impurities can largely be divided into two groups. The first, including most gases, are present immediately after their use in the machine; the second group includes those elements that are retained on plasma facing surfaces within the vessel. Most of these are metals, for which a systematic behaviour is found. Influxes due to metallic dust particles behave more like the elements of the first group. The origin of the impurities where this is known is given as well as details of the systematic behaviour, including differences due to the line-of-sight of the observing spectrometer. A clear difference is seen when the discharge fuel is H and this has implications for tritium and deuterium-tritium operations.

This paper presents the use of a deformable mirror (DM) configured to rapidly refocus a microscope employing a high numerical aperture objective lens. An Alpao DM97-15 membrane DM was used to refocus a 40x/0.80 NA water-immersion objective through a defocus range of -50 to 50 microns at 26.3 sweeps per second. We achieved imaging with a mean Strehl metric of > 0.6 over a field of view in the sample of 200 x 200 microns over a defocus range of 77 microns. We describe an optimisation procedure where the mirror is swept continuously in order to avoid known problems of hysteresis associated with the membrane DM employed. This work demonstrates that a DM-based refocusing system could in the future be used in light-sheet fluorescence microscopes to achieve video-rate volumetric imaging. Keywords: adaptive optics, remote refocusing, light-sheet fluorescence microscopy, deformable mirror